Universal sponge mop head



Dec. 5,1967 R.| .AE$LER AL UNIVERSAL SPONGE MOP HEAD Filed March 10,1967 N m m? NAP/0W W55 WADW/ p. WM 5 United States Patent M 3,355,844.UNIVERSAL SPONGE MOP HEAD Roger L. Abler, White Bear Lake, and John R.Anderson, Maplewood, Minn., assignors to Minnesota Mining andManufacturing Company, St. Paul, Minn., a corporation of Delaware FiledMar. 10, 1967, Ser. No. 622,128 7 Claims. (Cl. 51-400) ABSTRACT OF THEDISCLOSURE A sponge mop head is adapted for attachment on the mountingplate of a mop frame having either screw or slide attachment means. Thesponge is adhered to a sheet metal or similar base plate which can beeither left intact for screw attachment or broken to permit longitudinalcompression of the sponge for slide attachment.

Background of the invention This invention relates to brushing,scrubbing, and cleaning implements, particularly to sponge mops.

Sponge mops have been Widely used by housewives for many years.Basically these mops involve a synthetic sponge, typically a block ofregenerated cellulose, having a base plate attached to the upper surfaceand provided with means for attachment to the mounting plate on a mopframe. Heretofore there have been two main types of construction, whichto a large extent have been mutual- 1y exclusive. In the first type, aone-piece rigid metal base plate was adhered to the upper face of thesponge body and provided with a plurality of holes. The correspondingmounting plate on the mop frame was provided with either holes orlongitudinally extending slots which coincided with the holes on thebase plate. Screws were then used to attach the mounting plate to thebase plate, slots providing a means for permitting expansion orcontraction of the sponge as it absorbed or released moisture. Exemplarymop heads of this type are illustrated in U.S. Patents 2,594,553 and2,663,042.

The second major type of sponge mop construction is effectivelyillustrated in U.S. Patent 3,188,676. A small metal plate is mountedadjacent each end on the upper face of the sponge body, the two platesbeing separated by a substantial distance. Each plate bears a slidemeans having a cross-section designed for engaging tabs which are struckfrom one face of the mounting plate on the mop frame. Spacing theslide-bearing plates apart not only permits the sponge to expand andcontract, the cooperative slide means moving longitudinally along thetabs, but also permits longitudinally compressing the sponge so that theslides can be positioned between the tabs and then moved outward to gripthem firmly. Although this arrangement is convenient in many respects,the sponge mop sometimes contracts so much when not in use that the headbecomes disengaged from the slides and falls off, to the extremeannoyance of the housewife.

The aforementioned U.S. Patent 3,188,676 suggests that the two separatedslide-carrying plates may be provided with holes, to permit mounting onmop frames of the type first referred to hereinabove. Although this istheoretically possible, the resulting product is not totallysatisfactory for either purpose. Since the greater portion of the spongebody is not connected to any rigid support, the mop tends to bow,distort, chatter, and provide irregular cleaning action, no matter whattype of mounting plate the mop frame has.

Summary of the invention The present invention provides a novel spongemop 3,355,844 Patented Dec. 5, 1967 head which is effective forinstallation on any of the major types of mounting frames presently inuse, and is specifically adapted for attachment to both of the typesdiscussed hereinabove. The invention provides a sponge mop in which acontinuous elongated base plate is attached to the sponge body over thegreater portion of its length, thus providing resistance to bowing,distortion, and chattering in use, as well as minimizing any tendencyfor the mop head to fall off a mounting plate of the slide type when thesponge dries out. The novel mop head is readily attachable to anymounting plate employing screws or similar means of attachment. At thesame time, this mop head has slide means mounted adjacent each end ofthe rigid base plate, corresponding to the mating tabs found on themounting plate of the other common type of mop head.

As originally supplied, the continuity of the base plate preventsattachment of both slide means to the complementary pair of tabs foundon a mounting plate. The base plate, however, is so constructed that itcan be separated at its mid-point and one plate portion slid over theother far enough to permit the slide means to fit between the pair oftabs on mounting plates of this type. At the same time, the novelconstruction of this device is such that a drying mop head, can notshrink sufficiently to become detached from the tabs. Further, evenafter the base plate has been separated into two pieces and installed inthe manner and for the purpose just indicated, the mop head can still beremoved and screwed to a mop frame of a different construction withoutsacrificing quality of performance.

Brief description of the drawing The invention will be better understoodwith reference to the acompanying drawing in which:

FIGURE 1 is a view in perspective of a presently preferred embodiment ofthe invention;

FIGURE 2 is a longitudinal cross-sectional view of the mop head shown inFIGURE 1, taken along sectional line 2-2 and looking in the direction ofthe arrows; and

FIGURE 3 is a rear elevational view of the mop head shown in FIGURE 1,illustrating the manner in which the mop head is manipulated tofacilitate installation on a mop frame mounting plate having tabs on onesurface thereof.

Description of preferred embodiment In the drawings, prismatic spongebody 11 is secured to one face of low density fibrous lofty abrasive mat12. To the upper face of sponge body 11 is adhered base plate 13,divided into left portion 13a and right portion 13b by a weakenedportion, or break line 14. Base plate 13 is secured to the upper face ofsponge body 11 by adhesive layer 15 throughout their coextensive areas,except for adhesive-free area 16, which extends from break line 14 underright half 13b, across the entire width thereof, for a short distance.The attachment of base plate 13 and sponge body 11 throughout most oftheir coextensive length provides firm connection of sponge body 11 tothe mop frame and minimizes any tendency of sponge body 11 to bow in'thecentral portion during use. Bowing is further minimized by lip 17, whichextends substantially at right angles to base plate 13, overlying therear face of sponge body 11 and tending to hold it in fixed position.

At spaced locations equidistant from break line 14 are pairs ofdepressed holes, 18a and 18b, 19a and 19b, 20a and 20b. These holes areadapted to receive self-tapping screws which are inserted throughcorresponding holes or slots in the mounting plate on the mop frame.

Also located on base plate 13 adjacent the ends thereof are slide means21a and 21b, each of which defines, in

cross-section a C-shaped channel corresponding to the tab on a mountingplate of a different type of mop frame. When the mop head is to beinstalled on the mounting plate of afra'me, of this type, it is grippedfirm ly and bent back and forth along brealc line 14, thereby separatingbase plate 13 into halves 13. and 13b. In order to facilitate,separation of plate 13 along break line 14, lip- 1 7 is notchedin theimmediately adjoining area. Since there is noadhesiveinarea lfi, platehalf 1312 is readily lifted above and slid pver plate half 1.311.111order to facilitate installation but nevertheless maintain the maximumresist ance, fobowirrg, it is desirable that adhesivere a ea 16 xt d lnswd al a d anc a mating but notgreatly exceeding the length of slidemeans 21a or 21 b,typically abou'tan inch As is shown particularlydnFIGURE}, the sliding plate half lSb or plate half ,15a longitudinallycompresses sponge body 11, permitting slidemeans 21a and 21b to iitbetween the doivnwardly extending tabs on a mop frame mounting plate(indicated in dashed linesh when plate halves 13a and 13b are returned totheir original position slide means 21;; and 21b engage thecorresponding pair of tab means.

Lowidensit'y abrasive product 12, .a suitable form of which is describedand claimed in US. Patent 2,958,593, m b a hered t th pon by any u t b nA particularly satisfactory technique is to embed it in one face of asponge-forming cellulosic massto a depth su ftieiently to ilet the masspartially surround fibers in the interface, regenerate the cellulose,and convert the mass to spongeforrn, all as describedand, claimed in US.rars rs pso ssans Show i l FIGURE 1, it may be desirableto havethe lowdensity abrasive 12 extend less t "n the full depth of sponge body 11,thereby keeping it normally out of'contact with the floor when the lowersurface of sponge body 11 is being used. When it is desired to subjectthe floor to more rigorous cleaning akiti'omth'e in'opheadmay'be'turneds'o'that' its front face, and therewith low derisityab'ra'sive pad 12,is lowermost. To minimize the possibility of iiiidersirable -scraping ofthefloorduring such'operationtheforward edge of base plate 13 shouldnotext'e'rid completely to'th'e forward face 'pldtefcomprisi'rig incombination:

a"thin'rigid"elorigate base plate'liaving two sides'a'nd two ends,

a ality of attaching means on said base plate "a'daptedfor cbnnectiontocorresponding means on a plurality of different mopframe mountingplates, t r V saidbaseplate having a weakened portion, extendnabe wem is sides approximately m y f tween it's ends, along which said baseplatemay be brgken into two substantially equi-din'iens a a rs t and a aprismatic sponge body'having two ends and a plurality of sides, v p Aatnleast oneof said sides being both longer and jnt ide tha a d in t a,

said one, side being adhered'to one face of said "base platesubstantially'throughout their 'eoexensive arfeas except,for"'anadhesive free portionv of said areas, said portion beingabout'o'ne inchlong" and the entire width ofsaid base' pla'te iuehdin "from saidweakened portiombeneath one of said substantiallyequi-dirnensiorialparts ofsziid base pla'te.

2. The mop head of claim 1 wherein the attaching means on the base plateinclude a pair of slide members having a C-shaped crosssection, locatedadjacent the ends of said base plate and adapted, when said base plateis broken in two along its weakened portion, to cooperatively slidablyengage tabs extending below the surface of a mop frame mounting plate,

and a plurality of holes, located on opposite sides of the weakenedcenter portion of the base plate, adapted to receive self-tapping screwsextending through the correspondingly positioned holes on a mop framemounting plate.

3. The mop head of claim 2 wherein the base plate has a lip extendingdownward from one side thereof and is so dimensioned and positioned onsaid one side of the prismatic sponge body that said lip extends overthe adjacent side of said sponge body.

4. The mop head of claim 3 wherein the lip is notched at the portionimmediately adjoining the weakened portion of the base plate.

5. The mop head of claim 4 wherein the sponge body has four sides, theside opposite that over which the base plate lip extends having a loftynonwoven fibrous low density abrasive-mat amxedt her'eto.

6. The mop head'of claim 5 whereinthe low density abrasive matterminates short of the lower edge'of the side to which it is affixed. I

'7. In a sponge mop head "of the type wherein one face of a syntheticsponge is adhered to'a rigid elongate base plate extending over a majorportion of said face, said base plate being provided with holes forattachment to a first type of conventional mop frame mounting plate,

the improvement which comprises: I

providing a generally centrally locatedbreak line extending across saidbase plate, I providing, adjacent each end of said base plate, anelongate slide means of appropriate dimensions and position to slidablyengage, in'a direction parallel to the length of said baseplate, one ofa spaced-pair of complementary downturned tab means on a second type ofconventional mounting plate, itnormally being impossible tosimultaneously engage both of saidslide means with both of s'aidtabmeans,

and adhering said base plate to said sponge face throughout theircoextensive areas except for a portion adjoining one side of said breakline acrossthe entire width of said base plate for adistanceapproximately equal to the length of one of said slide wherebysaid mop head can eitherb e directly attached with screws to a mountingplate-of said firsttype, or attachedto a conventional mounting plate ofsaid second type by breaking saidba'se platealong said-break line,

sliding'the unadhered portion or one half of said base plate over theother half "or said base plate to longitiudinallyg compress the spongeand-permit positioning the pair of slide means on' said base platebetween theopair of tab means on 'a' mountin plate of said second'type,

'aid then sliding the pair of slide means apart, "thereby engaging eachslide 'rneans witha'corresp'onding tab 'DANIELTBLUM,PfintaryEfibafiriiigr,

1. A SPONGE MOP HEAD, DESIGNED FOR INSTALLATION ON A WIDE VARIETY OFSPONGE MOP FRAMES HAVING A MOUNTING PLATE, COMPRISING IN COMBINATION: ATHIN RIGID ELONGATE BASE PLATE HAVING TWO SIDES AND TWO ENDS, APLURALITY OF ATTACHING MEANS ON SAID BASE PLATE ADAPTED FOR CONNECTIONTO CORRESPONDING MEANS ON A PLURALITY OF DIFFERENT MOP FRAME MOUNTINGPLATES, SAID BASE PLATE HAVING A WEAKENED PORTION, EXTENDING BETWEEN ITSSIDES APPROXIMATELY MIDWAY BETWEEN ITS ENDS, ALONG WHICH SAID BASE PLATEMAY BE BROKEN INTO TWO SUBSTANTIALLY EQUI-DIMENSIONAL PARTS, AND APRISMATIC SPONGE BODY HAVING TWO ENDS AND A PLURALITY OF SIDES, AT LEASTONE OF SAID SIDES BEING BOTH LONGER THAN WIDER THAN SAID BASE PLATE,SAID ONE SIDE BEING ADHERED TO ONE FACE OF SAID BASE PLATE SUBSTANTIALLYTHROUGHOUT THEIR COEXTENSIVE AREAS EXCEPT FOR AN ADHESIVE-FREE PORTIONOF SAID AREAS, SAID PORTION BEING ABOUT ONE INCH LONG AND THE ENTIREWIDTH OF SAID BASE PLATE EXTENDING FROM SAID WEAKENED PORTION BENEATHONE OF SAID SUBSTANTIALLY EQUI-DIMENSIONAL PARTS OF SAID BASE PLATE.